https://bugzilla.kernel.org/show_bug.cgi?id=151491 Fischreiher (mfe555@xxxxxx) changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |mfe555@xxxxxx --- Comment #4 from Fischreiher (mfe555@xxxxxx) --- I have a similar or same problem on a Linux based Enigma2 set-top box - ext4 - kernel 4.8.3 - bigalloc enabled - cluster size of 262144 In normal use of the set-top box, the free space lossage is 10s of Gigabytes per day. The problem can be easily reproduced: When creating a fresh file, there is a significant difference in file size (ls -la) and disk usage (du). When making two copies of the file .. gbquad:/hdd/test# cp file file.copy1 gbquad:/hdd/test# cp file file.copy2 gbquad:/hdd/test# ls -la -rw------- 1 root root 581821460 Nov 1 18:52 file -rw------- 1 root root 581821460 Nov 1 18:56 file.copy1 -rw------- 1 root root 581821460 Nov 1 18:57 file.copy2 gbquad:/hdd/test# du * 607232 file 658176 file.copy1 644864 file.copy2 ... all three files show an overhead in the ~10% range, and the overhead is different for these files although their md5sums are equal. When deleting a file (rm), the overhead remains occupied on the disk. For example, after deleting "file", "df" reports approx. 581821460 more bytes free, not 607232 kbytes more free space. The overhead (607232 kB - 581821460 B = approx. 39 MB) remains blocked. When unmounting and mounting again, the blocked space becomes free again, and in addition the overhead of those files that were not deleted also disappears, so that after a re-mount the 'file size' and 'disk usage' match for all files (except for rounding up to some block size). I found that echo 3 > /proc/sys/vm/drop_caches seems to detach the blocked disk space from the files (so that 'du file' no longer includes the offset), but it does not free the space, 'df' still shows all file overheads as used disk space. -- You are receiving this mail because: You are watching the assignee of the bug.
